Abstract
Techniques used for measuring endogenous and exogenous energy expenditure during exercise often require the use of indirect calorimetry along with collection of expired air (breath) into a mixing chamber for extraction of breath samples for 13C breath analysis (by isotope ratio mass spectrometry) (O’Hara et al. 2017; King et al. 2018). When collecting expired air into a mixing chamber an additional mouth piece and tubing is attached to the online gas analysis mouth piece. This has the potential to alter the flow rate through the online gas analyser and therefore alter the measurements.
PURPOSE: To investigate the use of an additional mouth piece and tubing used for expired air collection to establish a reliable and accurate methodology to be used in future metabolic research concerning the use of labelled (13C)
substrates.
METHODS: 7 healthy male participants (27 ± 6 years) completed 3 conditions on a cycle ergometer, in a randomised order. The conditions were; 1: 5 min indirect calorimetry plus mouth piece and tubing (MT), 2: 5 min indirect calorimetry followed by 5 min (IC1) indirect calorimetry plus mouth piece and tubing (MT1), 3: 5 min indirect calorimetry plus mouth piece and tubing (MT2) followed by 5 min indirect calorimetry (IC2). HR, VT, VE, V̇O2 and V̇CO2 were measured during each 5 min section of the trials. Calculations for whole body carbohydrate (CHO) and fat oxidation and total energy expenditure (TEE) were performed. Data was analysed using repeated measures ANOVA and post hoc analyses where a main effect was observed. Statistical significance was set at p< 0.05.
RESULTS: VT was significantly (p= 0.002) higher in MT2 compared with IC2. V̇O2 was significantly different between conditions (p< 0.05) with values of 2.43 ± 0.34, 2.31 ± 0.35, 2.56 ± 0.32, 2.66 ± 0.32 and 2.41 ± 0.33 L.min-1 in MT, IC1, MT1, MT2 and IC2, respectively. HR was significantly lower in MT (144.43 ± 12.84 beats.min-1) compared with MT2 (151.86 ± 12.89 beats.min-1; p= 0.003) and IC2 (151.86 ± 12.43 beats.min-1; p=0.001) and significantly lower in IC1 (143.29 ± 12.89 beats.min-1; p=0.003) compared with MT2. There were no differences between conditions for VE, V̇CO2, CHO and fat oxidation and TEE.
CONCLUSION: There were significant differences between conditions for VT, V̇O2 and HR, suggesting methodological considerations for future research.
PURPOSE: To investigate the use of an additional mouth piece and tubing used for expired air collection to establish a reliable and accurate methodology to be used in future metabolic research concerning the use of labelled (13C)
substrates.
METHODS: 7 healthy male participants (27 ± 6 years) completed 3 conditions on a cycle ergometer, in a randomised order. The conditions were; 1: 5 min indirect calorimetry plus mouth piece and tubing (MT), 2: 5 min indirect calorimetry followed by 5 min (IC1) indirect calorimetry plus mouth piece and tubing (MT1), 3: 5 min indirect calorimetry plus mouth piece and tubing (MT2) followed by 5 min indirect calorimetry (IC2). HR, VT, VE, V̇O2 and V̇CO2 were measured during each 5 min section of the trials. Calculations for whole body carbohydrate (CHO) and fat oxidation and total energy expenditure (TEE) were performed. Data was analysed using repeated measures ANOVA and post hoc analyses where a main effect was observed. Statistical significance was set at p< 0.05.
RESULTS: VT was significantly (p= 0.002) higher in MT2 compared with IC2. V̇O2 was significantly different between conditions (p< 0.05) with values of 2.43 ± 0.34, 2.31 ± 0.35, 2.56 ± 0.32, 2.66 ± 0.32 and 2.41 ± 0.33 L.min-1 in MT, IC1, MT1, MT2 and IC2, respectively. HR was significantly lower in MT (144.43 ± 12.84 beats.min-1) compared with MT2 (151.86 ± 12.89 beats.min-1; p= 0.003) and IC2 (151.86 ± 12.43 beats.min-1; p=0.001) and significantly lower in IC1 (143.29 ± 12.89 beats.min-1; p=0.003) compared with MT2. There were no differences between conditions for VE, V̇CO2, CHO and fat oxidation and TEE.
CONCLUSION: There were significant differences between conditions for VT, V̇O2 and HR, suggesting methodological considerations for future research.
| Original language | English |
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| Publication status | Unpublished - May 2022 |
| Event | American College of Sports Medicine: Annual Meeting - USA, San Diego Duration: 31 May 2022 → 4 Jun 2022 |
Academic conference
| Academic conference | American College of Sports Medicine |
|---|---|
| City | San Diego |
| Period | 31/05/22 → 4/06/22 |